This invention relates generally to filter assemblies and, more particularly, to several embodiments of a universal type filter assembly which is adaptable for use in compressor assemblies associated with oxygen concentrators, ventilators, and other medical applications in the home care medical equipment industry, which filter assemblies include means for adjustably controlling the air flow requirements into the unit based upon the particular needs of the compressor assembly to which it is attached. The present filter assemblies also include baffle means configured for noise attenuation.
Oxygen concentrators, ventilators, and other medical applications which utilize compressor assemblies are commonly used in the care of respiratory patients, particularly, in the home care environment, to provide sufficiently high purities of oxygen to the patient without using high pressure tanks of liquid oxygen. Oxygen concentrators and the like utilize ambient atmospheric air as their source of oxygen in conjunction with an absorption system to separate oxygen from the other gases found in the air and to provide that oxygen in concentrated form to the patient. Atmospheric air typically includes approximately 80% nitrogen and 20% oxygen. Nitrogen is typically absorbed by the absorption system and is retained therein until subsequently purged.
Typically, atmospheric air is drawn into an oxygen concentrator, ventilator, or other breathing apparatus from the ambient environment and such ambient air is then passed through a filter assembly to remove dust and other contaminants from the ambient atmospheric air. The filtered air is then pressurized by a compressor and, in the case of an oxygen concentrator, is then introduced into the absorption system. Once the compressed air is introduced into the absorption system, the nitrogen is selectively absorbed and released to atmosphere leaving the residual oxygen available for patient use. Oxygen concentrators typically produce an oxygen concentration usually in the range of 90-95%.
Use of an effective filtration system for purging contaminants from any liquid or gas is always important for a multitude of obvious reasons. Properly and effectively filtering the incoming ambient air before it is compressed and introduced into the absorption system of an oxygen concentrator, or before it is provided directly to the patient, is always important because effective filtration not only improves the overall efficiency of the oxygen concentrator, ventilator or other breathing apparatus but it also improves and increases the oxygen concentration provided to the patient. Poor filtration of the incoming air also subjects the oxygen concentrator, ventilator, or other similar apparatus and its associated compressor to excessive wear from particles which contaminate the system thereby decreasing service life while increasing maintenance.
As a result, a wide variety of different types of filter assemblies are utilized in conjunction with a wide variety of different types of compressors associated with all types of breathing apparatus such as oxygen concentrators, ventilators, and other similar equipment. These filters are specifically designed to both mate with the particular oxygen concentrator or other breathing apparatus and to provide at least the minimum required air flow to the compressor for proper operation of the breathing apparatus. This means that a properly designed filter assembly must be mated with a particular oxygen concentrator or other breathing apparatus based upon the air flow requirements of the oxygen concentrator or other breathing apparatus.
Still further, the type and size of compressor associated with the oxygen concentrator or other breathing apparatus likewise determines the overall oxygen flow rate capacity as well as the level of noise produced by the system during operation. In general, large compressors required for providing higher rates of oxygen require a filter assembly designed to provide the necessary air flow through the filter and to the compressor for proper operation. Also, large compressors required for providing higher rates of oxygen can be quite noisy. As a result, acoustic dampening and other noise attenuation means are sometimes provided in an effort to insulate and dampen the noise from the compressor. Since oxygen concentrators, ventilators and other similar breathing apparatus are typically used at home, or in a hospital or nursing home type environment, noise generation can be a problem. Often times, despite the efforts made to dampen the noise associated with various compressors, the sound generated is still often excessive. Noise attenuation is therefore likewise always an issue in designing effective filtration systems for use in the home care medical equipment environment.
It is therefore desirable to provide a universal type filter assembly which not only improves the air filtration process to the absorption system of an oxygen concentrator or other compressor assembly, but which likewise includes means for adjustably controlling the air flow requirements to the compressor assembly such that the same filter assembly can be used with a plurality of different types of compressor assemblies having different air flow requirements. It is also desirable to provide a universal type filter assembly which likewise includes means to reduce and dampen the overall noise level associated with the operation of the oxygen concentrator, ventilator, or other compressor assembly.
Accordingly, the present invention is directed to a universal type filter assembly which overcomes one or more of the problems as set forth above.